export function convertEmptyToNull(obj) {
    for (let key in obj) {
      if (Object.prototype.hasOwnProperty.call(obj, key)) {
        if (typeof obj[key] === 'object' && obj[key] !== null) {
          convertEmptyToNull(obj[key]); // 递归遍历嵌套对象
        } else if (obj[key] === '') {
          obj[key] = null; // 将空值转换为null
        }
      }
    }
  }